But Mourinho insisted Costa’s demeanour around the squad is not that of a player seeking to leave.

“He’s the guy responsible for everything good we have in the dressing room,” the Chelsea boss said after the Blues ended their Premier League-winning season with a 1-0 win over Sydney FC on Tuesday afternoon.

“He’s so happy, so funny. He enjoys every minute and is the happiest guy in the dressing room. If this is unhappiness I’m happy with that. He was not happy with the news.”

And Costa also weighed in on the debate, insisting he will be a Chelsea player next season as the team look to build on last season’s Premier League victory.

The 26-year-old told Chelsea TV: “It’s quite a simple answer. It’s always a bit more difficult for adaptation in the first season, but I have no reason to leave this place, I love it, the fans love me and I want to stay.

“It’s really good to come in the first season and win two things. It’s really important and next year I’ll be ready to come back and hopefully win a couple more trophies.”

Mourinho was pleased with Costa’s attitude as Chelsea, who fielded a host of regulars including Eden Hazard and John Terry, brought down the curtain on a long season in front of a crowd of 83,598 in Sydney, with Loic Remy netting the game’s only goal.

“Diego tried, but we didn’t want to take any risks. I told him to give the fans at least half an hour and he played until the 40th minute. We felt that was enough,” Mourinho said.